Being famous and struggling with infertility has got to be hard, but at least when you're a celebrity human, you can more or less keep the details of your experience to yourself. That's not the case for celebrity pandas Mei Xiang and Tian Tian, who have lived together at the National Zoo in Washington, D.C., for 10 years and so far have only produced one baby.

The zoo focuses heavily on studying panda reproduction, and they've been trying to get Mei Xiang (pictured above) knocked up for the past six years. In 2005, she gave birth via artificial insemination to Tai Shan. (He went back to live in China in 2010, where he is now part of a breeding program.) But the last five attempts to impregnate Mei Xiang have failed, and she's thirteen years old now. Thus her chances of reproducing further aren't looking so good. What's worse is that since she and Tian Tian have been unable to conceive a second time, there's talk of replacing Mei Xiang with a new, hopefully more fertile panda. No pressure, Mei Xiang!

This weekend Mei Xiang went into heat, and she and Tian Tian were placed together in the panda compound, which sounds very romantic. Sadly, they were unable to mate naturally—something the pair has been "consistently been unable to accomplish"—and so zoo employees artificially inseminated Mei Xiang instead. (They also, ahem, live-tweeted the whole thing, if you're interested.) If no cub results from this procedure, they may replace Mei Xiang, even though they have a lease on her from China through 2015. But the tough old gal may yet get a break. The zoo has said they'd consider replacing Tian Tian instead because he's proven to have an "inexpert mating ability." Ouch, it's tough out there for a panda. Let's keep our fingers crossed for these bears.